Lesson objective: Add and subtract to determine if equations are true or false.

This lesson helps to build fluency with comparing values on both sides of the equals sign. Balances, ten strips, and connecting cubes are used here because they allow students a visual representation of the values they are being asked to compare. This work develops students' understanding that an equation is true if both sides of the equals sign have the same value, and false if the two sides have differing values.

Students engage in Mathematical Practice #2 (reason abstractly and quantitatively) as they compare the two sides of an equation to determine if the equation is true or false. Before students typically only saw true equations, with one operation. This task will guide students toward flexibly thinking about numbers and operations within equations.

**Key vocabulary:**

- balance
- connecting cubes
- counters
- determine
- equal
- equals sign
- equation
- math tools
- ten strip
- value

******Special materials needed:**

- balance
- connecting cubes
- counters
- ten strips